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Biomedical subjects

J W Gaskill

Publications and source records attributed to J W Gaskill.

5 recordsLinked to original sources
PubMed1990

Contrast information of digital imaging in laser film digitizer and display monitor.

A 10-bit or 12-bit gray scale is provided in commercial laser film digitizers. The true contrast resolution on the digitized image within a laser spot area of 200 microns in diameter is limited by both the quantum mottle and instrumentation noise. In this report, we investigated the mean value, standard deviation, and adjacent pixel correlation coefficient on a calibrated step wedge film with two laser digitizers. The results were disappointing, because we found that the evaluated contrast information is inferior to the manufacturers' specifications. On the output side, the brightnesses of different gray levels from a clinical monitor were measured with a narrow angle luminance probe and evaluated by a brief human perception study. In addition, the implications for teleradiology applications are discussed.

Data Display↗
PubMed1983

Physician attitudes toward the competence of general diagnostic radiologists: survey and implications.

Responses to a questionnaire were obtained from 1,539 physicians in 15 medical specialties to measure their attitudes toward general diagnostic radiologists in regard to their medical knowledge and professional competence as consultants. The data were evaluated in terms of the demographic profile of the respondents. Among the detailed results obtained, it was determined that only 8.1% of all physicians believe general diagnostic radiologists are poorly informed about disease processes, but 25% believe that these radiologists need more subspecialty training to be valuable as consultants to them. Physicians who do their own radiographic/sonographic examinations believe general diagnostic radiologists to be unimportant twice as often as do physicians who refer their patients to radiologists (28.2% vs. 14.5%). Most physicians (78%) believe that diagnostic radiologists perform unique functions in hospitals, while only 38% believe this to be true in the office setting. Consistent with this is that physicians practicing primarily in hospitals believe diagnostic radiologists need more training than do the primarily office-based physicians (29.6% vs. 16.8%). Of the specialists surveyed, orthopedic surgeons, neurosurgeons, cardiologists, and neurologists consistently had the lowest opinion of general diagnostic radiologists as consultants. In each of these specialties, less than 30% believed that general diagnostic radiologists are indispensable in the hospital setting. Also, younger (less than 45 years) physicians feel less dependent on general diagnostic radiologists than do older physicians. For example, twice as many younger physicians (17.3% vs. 7.9%) believe that diagnostic radiologists perform few or no unique functions which they cannot do themselves.

Ambulatory Care↗